Prototyping of a highly performant and integrated piezoresistive force sensor for microscale applications

Bilal Komati (1) , Joël Agnus (1) , Cédric Clévy (1) , Philippe Lutz (1)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)

In this paper, the prototyping of a new piezoresistive microforce sensor is presented. An original design taking advantage on both mechanical and bulk piezoresistive properties of silicon is presented and enables to easily fabricate a very small, large range, high sensitivity with high integration potential sensor. The sensor is made of two silicon strain gages for which widespread and known microfabrication processes are used. The strain gages present a high gage factor which allow a good sensitivity of this force sensor. The dimensions of this sensor are 700mm in length, 100mm in width and 12mm in thickness. These dimensions make its use convenient with many microscale applications notably its integration in a microgripper. The fabricated sensor is calibrated using an industrial force sensor. The design, microfabrication process, and performances of the fabricated piezoresistive force sensor are innovative thanks to its resolution of 100nN and its measurement range of 2mN. This force sensor presents also a high signal to noise ratio, typically 50dB when a 2mN force is applied at the tip of the force sensor.

Domaines: Micro et nanotechnologies/Microélectronique

Bilal Komati, Joël Agnus, Cédric Clévy, Philippe Lutz. Prototyping of a highly performant and integrated piezoresistive force sensor for microscale applications. Journal of Micromechanics and Microengineering, 2014, 24, pp.1-19. ⟨10.1088/0960-1317/24/3/035018⟩. ⟨hal-00958816⟩